Oil a 7 to 10-inch springform pan or four 4-inch springform pans. (See above paragraph for size pans.) Then, line the bottom with parchment paper and oil the top of the paper. Preheat the oven to 350°F.
While the mix is cooling, sift together the cake flour blend, cocoa, and salt onto a sheet of wax paper or parchment paper; set near the mixer.
Bake a single recipe in 4-inch pans for 25 minutes. Bake a single recipe in a 7-inch pan for about 35 minutes. Bake a double recipe in three 8-inch pans for 25 minutes. ***No matter which version you make, bake the cakes until they spring back when pressed lightly with your fingertips and the cake moves away from the sides of the pan.
If necessary, use a knife or small spatula to loosen any stuck-on cake from the springform ring and remove the ring.
Once cool, base any hard edges with simple syrup, if needed.
If desired, slice each layer in half, horizontally, using a serrated knife, using a sawing motion. (To do this easily, slice into the cake about 1-inch all the way around. Then, wrap waxed dental floss or cotton string into the crevices. Criss-cross the ends and pull in opposite directions until the entire cake is sliced in half or thirds (whatever you’re striving for). Alternatively, after slicing into the cake about 1 inch, you may use the same knife to slice all the way through the cake.
https://glutenfreerecipebox.com/gluten-free-chocolate-sponge-cake/